The former head of the building industry watchdog has mocked Labor government claims that it was unaware of the CFMEU’s underworld connections, saying he repeatedly alerted parliament to union links with bikies and organised crime over two decades.

The ex-commissioner of the Australian Building and Construction Commission, Nigel Hadgkiss, called for the return of an industry watchdog, with new punitive powers against unions to tackle an underworld takeover of the construction industry.